Can Tyvek Be Used On Interior Walls? (Solved)

Tyvek has many uses. In the construction industry, Tyvek is used as a house wrap. Features such as being water-repellent, durable, tear-resistant, and breathable make Tyvek one of the best house wraps on the market.

For construction purposes, you will often see Tyvek used on the exterior of a building. But can it still offer the above benefits when used on interior walls? This will be our main topic of discussion.

“Tyvek” by Ryo Chijiiwa, Flickr is licensed under CC BY 2.0

Should Tyvek Be Used on Interior Walls?

According to Dupont, the manufacturer of Tyvek, this house wrap should not be used on interior walls. Tyvek is designed specifically for use behind exterior walls.

Regarding building materials, it’s always advisable to stick to the manufacturer’s instructions. If you consider using Tyvek on the interior walls, you must comply with the manufacturer’s instructions.

What are the Risks of Using Tyvek on Interior Walls?

The biggest risk of using Tyvek on interior walls is that it can lead to mold issues. I know you are wondering how that is possible, considering Tyvek creates a permeable barrier that allows vapor to pass through. Here is an in-depth explanation of what will happen when you use Tyvek on interior walls.

First, you have to understand how Tyvek works. When installed as a house wrap, Tyvek prevents water in liquid form from passing through the surface. However, it also allows moisture to be dissipated from the walls, thus allowing the building to breathe.

The dilemma of installing Tyvek on interior walls is that it will allow moisture from outside to pass through the Tyvek and settle on interior sheathings such as OSB, plywood, or drywall. As a result of moisture buildup, mold will slowly start to develop.

The ideal place for you to install Tyvek is on the exterior walls. On an exterior wall, Tyvek will prevent water from leaking or seeping through.

At the same time, it will allow the walls on the inside to breathe and get rid of excess moisture, which may otherwise lead to mold growth. When you use Tyvek on interior walls, you are welcoming mold into your home.

What If It’s Installed Backward on an Interior Wall?

If you are into DIY, you may consider installing the Tyvek backward on an interior wall. The outcome will almost be the same. Moisture is also present indoors, especially in rooms such as kitchens and showers.

If there is Tyvek installed backward, moisture coming from the inside will be allowed to pass through, and it can get trapped beneath the walls and cause mold development. It’s a lose-lose scenario irrespective of whether you install it facing the front or back.

Should Tyvek Be Used on the Cold or Warm Side?

The cold side is the exterior part of the home. When used here, you will reap the full benefits of Tyvek. It will remove moisture from the inside of the walls and prevent water leaks from passing through.

On the warm side, which is the interior, you should go for a material that doesn’t allow vapor to pass through. This protects against rot or mold growth by preventing moisture from getting trapped inside the walls.

Does Tyvek Only Transmit Water Vapor One Way?

Tyvek’s ability to let water vapor pass through is one of the crucial features that determines why it shouldn’t be used on interior walls.

From the above description of what will happen when Tyvek is used on interior walls, you may be wondering, does this product transmit water vapor one way?

Out of the many construction materials made, Tyvek is undeniably one of the most innovative. A membrane that is water-repellent and permeable is indeed a work of art.

When you check how Tyvek is designed, the front surface works by ensuring liquid water doesn’t pass through. It’s therefore water-repellent. The back material enables vapor to pass through.

From the manufacturer’s description, Tyvek only allows vapor to be transmitted one way. But from a scientific point of view, if Tyvek can let moisture pass through from the back.

Then it means that moisture on the front end will also pass through. Before using Tyvek on your interior walls, this is something that you have to think about in depth.

You Won’t Enjoy Tyvek’s Water-repellent Capabilities When You Use It on Interior Walls

The other problem with using Tyvek on interior walls is that you will not enjoy the water-repellent feature. On an interior wall, there should be no water leaks.

And if there are, they need to be fixed asap before mold starts to grow. Tyvek’s main use in the construction industry is to repel water from damaging building materials. You will not benefit from the water-repellent capabilities when used on an interior wall.

Is Tyvek a Substitute for Insulation?

Tyvek can act as an air barrier. For a home that is not insulated, you may consider using Tyvek as an alternative. Unfortunately, Tyvek is not an insulating material and lacks the property of insulating material.

Is Tyvek a Vapor Barrier?

Tyvek is the exact opposite of a vapor barrier. Instead of preventing moisture from passing through, Tyvek allows moisture to pass through. And that’s why it’s the wrong material to use on an interior wall.

Even if you have some excess Tyvek after installing it on the exterior walls, do not be tempted to use them as an alternative. Doing so will result in a complete failure of the materials on the interior walls. Also, mold is a serious health risk.

What’s the Best Material to Use on Interior Walls?

If you are interested in a vapor barrier for interior walls, you should choose polyethylene sheeting. This vapor retarder does an incredible job of sealing walls.

When you use poly under drywall, it creates a tight seal that moisture can’t pass through. This ensures that there is no vapor between the walls, leading to mold development.

Is It a Good Idea to Tyvek on Interior Walls?

Without even making an explanation, it’s a bad idea for you to Tyvek on interior walls. If this thought has crossed your mind, it should be ignored immediately.

One of the perks of research is that it helps you avoid landing yourself in trouble. Here are reasons why installing Tyvek on interior walls is a bad idea.

A typical vapor barrier has a perm rating of less than 1. On the other hand, Tyvek has an extremely high perm rating because it’s designed to let moisture pass through.

When you use a product such as Tyvek with such a high perm rating, moisture will pass through, and if the outside is pretty cold, it will condense into water.

The bottom line is that Tyvek doesn’t belong on interior walls. You are better off using a suitable vapor barrier.

Should You Use Tyvek in Areas that Experience Warm-Humid Climates?

The assumption of using Tyvek in interior walls on homes in warm-humid climates is that the temperature outside is not cold and will not condense vapor passing through the Tyvek.

It doesn’t matter the climatic conditions your home is exposed to. Using Tyvek on interior walls is a big NO. Property owners should adhere to the correct building codes and standards.

Even in warm climates, the moisture passing through the Tyvek will gradually cause dampness on the interior walls. Better to use the correct materials and avoid problems that will manifest in the future.

What about FlexWrap?

FlexWrap is a self-adhering butyl flashing that is often used alongside Tyvek. Unlike Tyvek, FlexWrap can be used on interior walls. It’s highly effective, especially on interior walls along door and window sills.

The perks of using FlexWrap are that it creates an air and water barrier. FlexWrap should only be used when necessary. For instance, if you are interested in sealing seams on an interior wall.

Is Tyvek a Crucial Part of an Interior Wall?

No. Tyvek is a product that should only be used for additional protection against water damage on exterior walls.

Many components make up a wall from the exterior to the interior. Fortunately, Tyvek isn’t one of them. There is no reason you should use it on any part inside your walls.

What is the Use of Tyvek?

Having ruled out that Tyvek shouldn’t be used on interior walls. We need to define the main uses of this product.

Tyvek is a synthetic material made of polyethylene fibers. It is resistant to aging and penetration of bacteria, water, and air.

It’s also quite breathable, and that’s why it’s one of the best house wraps. Besides being used as house wraps, Tyvek can make PPEs, sterile products, industrial packaging, cargo covers, and modern envelopes.

There are many uses for Tyvek. But when it comes to home construction projects, Tyvek is an excellent house wrap that will protect the materials from water damage and ensure they can ‘breathe’.

All these benefits are only applicable when Tyvek is used on exterior walls.

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